Plow and jet-elevator dredge



Nov. 6, 1928. 1,690,239

J. M. NICOL PLOW AND JET ELEVATOR DREDGE Filed April 12, 1926 4 Sheets-Sheet 1 MAM/41. HATCH/1R6! IN VEN TOR I ATTORNEYS Nov. 6, 192&

J. M. NICOL PLOW AND JET ELEVATOR DREDGE Filed April 12, 1926 4 Sheets-Sheet 2 IN VEN TOR Nov. 6, 1928. 1,690,239

J.M. N ICOL PLOW AND JET ELEVATOR DREDGE Filed April 12, 1926 4 Sheets-Sheet 3 INVENTQR A TTORNE Y6 Nov. 6, 1928. V 1, 90,239

J. M. NICOL PLOW AND JET ELEVATOR DREDGE Filed April 12, 1926 4 Sheets-Sheet 4 41 W INVENTOR I WI. 71404? Patented Nov. 6, 1928. V

@A E Tm-m.

Jofifiiglsl conm ma s, or Mimi VALIEFS'E, minimise;

My invention relates to the art of excztvatmg under watergwhmh is termed dredging,

and has as an objeetthe providing ofa 0011M binetion of methods of excavating and clevat- 111g materials-not lnt-hertoused andthat can be applied to both industrial dredging as perhaps the greatest excavating power, but

the material iswha-ndledintermittently, the mechanism eonslstlngi, essent ally. of 'a single bucket at the .endgofatliedipper arrn p The dippergdredge is; thewonly one in actual use that hzise true shovel diggingaetiomirr that the meolmnismfldmits of forcifigtheemi 1 downward, while the gable pulls the dipper forward and lintowthe inaterial to excavated. Conversely thierm'een hefo-rclrhly rarsed, so as to free the dipper whenmakmg a swing; hack for; a new but. In thekpre'sent suction dredgesf there Is a continuous action, but the lifting power? is limited totheva cuuin ereatedgby'ithepump and this vaonmn'ean easily: be broken I when the priming is. lost.

' Furthermore, the ascending Veloeityin the SHCUODPIPQ canrarely he,melntmnedat or above filtered-feet per: second, whicl1, will not maintain heavy minerals in suspension;

: My invent-lonlms Jas its pllllfCl'pfll object the prov sion of a h sttetlon dredge operait 11g w ith agpowerftdWater jetthat will ;r

heevymineral particles and operate commuonsly with e eentlnuous yawn-1n ther object there, is the Pl'QYlSlQlI of a oom- 1 bination of the aforesaid'j et nechanis jx; with anexeayarting men'iber ha ving'e full; a etionflhat 1s, having a sw nging motlon-iop I terielsi These and ot novel w 'd' ill'ldjbcl ckgllfld el ,full power control, and atthe stupetirnge dowmy qrd thrust and up; ward glifh b othl under full power QODU' Ol.

A t t rrtl ler eot toldewise, n frelationto the eh ove mecl'ianisms, a plowshaped and plowaetio n putting shoe, fitted with protective grid openings to ,GXClL de the eoarsest n a- I J r objectslareeceo nplished in thef following spe-eifieatiolr and dmwingsfwl ohjdeseribe the preferred emhodirneiitof my in vention M p forrn is a trunnion on which swings thefdlgpressure hy end stow AND mem vmoe DREDGE.

Application m'au 'rirm, 1926. Serial No. 101,228"

In the drawings,-" 7 v A Fig. 1 represents aside View or elevation oftl' 1e'inz1 in partsof the pontoonand dredge; 2 represents .a side View or elevation of the pontoon and dredge, showing the auxil mry grab hueketsend stuelrerp i Fig. 3 plunNie-w of Fig. 2; i 4 is an end iewntherrol; r levation, partly in section t p 7 ielnhly, viewing it fl'OlIl'dlllQ how of the'pont on toward the stern;

Fig. 6 is a plan or topgyiew er Fig.7 is (111 end View of Fig-qfi lookingto- V ward the how, that is, from thele'ft end of ljig. 8 iszt srationalelevation'of-the 51m and, jet .rneehiruisin; l l v Fig 9 is a front elevation thereof; -Figi' is :1 section of Fig f8'onthe line 1O+ 1O; a nd It I i Fig. 11 a top orpla-n View of Fig: 8. .d

Inseid figures there isshown a 15 m pontoon l floated ineprepared pond, this poiitoonbeing provided with vertical guide tower 2, forming at the same time a-jbre ced gaunti y to carry *the sheaves for the cables and to as: at mast; for the grab elemshell booms onl either side. ,In this guic' l; toiver there is provided anpp'er fixedfseetiong *qf l epie p-de p pe nd 1 o r ,sle tlon 4 connecting to rotating; elbow joined with one arm of tl'letrunni on 011 the plettorin,

to he'described i This ,up-east pipe delivers dredge. Behind this up-east pipe (as viewed in F g-L1) 1s a. ,dowrrcast pressure eter telescoping pipe 6 whiclrconnects at its top to pipe-Treceix ing pressure water from a cen' -tugzrl pump 8 Whichis driven by me e? 'l el e e wpin Pi e amids- ,tge nedf to th e vertieally .rnov'ztble I platform sliding in rertical guides, sulc hdell, 12;,fby means of shoes 13.; l-leloxyfthe morahlefpl it ging arm 14 eontlt'iifiiigWithin it the high tulle supply down-east. pipe 15 e up rast pipe orhyd 'uuliej elevator l6 "1 elbow 17 mounted in 1 suitable bushingirt 18,- and connecting throtrghj another elbow 19 tothe telescoping i pip'es 3 and t which del yer to the mater al dlSQhttlTgQL; The pres sure water pipe 15 connects, through swing he pipe116 Connected to .ajsivingihg (ill ing elbow 20 mounted in a suitable bushing 21, to elbow 22, which in turn connects to pipe 6', thus forming a trunnion for the water pipe 15. By means of these two trunnions the entire digging arm 1% beneath the platform can swing back and forth from any position in which the platform may be placed. The lower initial digging position of the arm 1-1 is shown in Fig. 1 and also the upper position near the end of the stroke when the platform is raised to the upper position, as shown at A. main cable 24 operating over the braced boom 25, adjustable for height, pulls the digging arm forward and is operated by a main hoist 26, the cable passing over sheave wheel 27. The braced boom is provided with various swivel anchor points at the forward deck so as to have further adjustability for position. A back-pull cable 28 is provided to draw the digging arm back, and is operated by a suitable winch 29.

In Fig. 2 isshown a stacker 30 with associated operative mechanism, and spuds 31 for fixing the position of the pontoon, thereby enabling it to operate on a radius. A hydraulic cylinder and piston 32 operate by means of cables 33, the sheave wheels 34, which lower and raise the said platform 10. A grab bucket 35 which may be provided on either side of the pontoon, as shown in Fig. 3, is hoisted over a boom 36 and operated in the usual manner through cables 37, etc.

Housing 38 is shown in Figs. 2 and 4.

Description of the plow and jet.

In Figs. 8 to 11 the plow and jet are shown in detail. The plow 39 is a. massive steel shoe having a shovel-shaped base at the front and a plow-shaped nose of steel 40. Grid openings 41 allow the finer material to pass into the interior of the plow but exclude the coarser minerals and rocks. The suction through the grid openings is created by the powerful water jet at the nozzle 42 which is bolted to a circular nozzle plate 43. The nozzle issupplied with pressure water from the pipe 15 through the bend 414-. A constricted throat l properly positioned with respect to the nozzle 42 operates in conjunction with the powerful jet of water to create a vacuum within the casing (which is generally designated by 46). The cable 24 is attached to the plow at 4.7 in any suitable manner and the cable 28 is likewise attached at 48.

Operation.

The dredge having been floated in a prepared pond, the grab buckets can be used to dig a sufficiently deep hole to allow the digging arm to be lowered into cutting position. If work is done in digging a channel or harher, the cutting plow need only be moved with relatively short strokes and at any required rate of advance, according as the material has to be dug or comes to the suction. In placer mining for old or stream tin, where digging against a milk of hard gravel, the digging arm can be swung through a full stroke, and if part of the gravel is above water level it can be brought up above the water and break-down bank, just as a steam shovel would do. On the return stroke the platform carrying the trunnion is raised, so as to allow of a free swing back and the back-pull cable 28 then comes into operation. hen the digging arm arrives in vertical position the platform is lowered and a new cut started. The lowering of the platform and heavy lllGCllflIllSll'l provides adownward thrustso that the plow digs in at the beginning of the stroke. The hydraulic clevator 32 raises the platform to the upper position 523 immediately preceding the back stroke of the arm 14 and thereupon releases the platform so that it may descend with suitable speed to dig in for the next stroke. The pontoon. would be controlled as to position by spuds and side lines, just as in standard dredging operations, the advance being a side swing for each succeeding out while working on a radius from one spud.

In this operation the hydraulic elevators do not lose their priming if exposed to'air suction as in the case of centrifugal dredging pumps. Furthermore the up-cast pipe can be crowded to carry a far larger proportion of solids, even up to or and the ascending velocity can be maintained at 20 per second, as against the velocity of 12 to 15 in suction pumps.

The above-described mechanism has distinct advantages over those heretofore used. The excavating power is due to the pull of the cable, as in a regular dipper dredge, and to the downward or outward thrust of the digging arm, but as the shoe is shaped like a plow, its cutting and excavating power in heavy ground is much greater than in a dip per dredge. All material small enough to go through the grid openings is immediately sucked in and elevated in a continuous stream whereas any material too coarse is shoved to one side by the curved face of the plow and can be handled by the auxiliary grab or clamshell dredge. In former suction drcdgcs excavation was effected by some form of auxiliary rotating head and the intake was caused only by the vacuum developed by a pump above water level. Any attempt to force the material to the suction in such devices might overload the power of the vacuum and cause the pump to lose its priming. Any attempt to attach the suction to a digging arm and bring the latter above the level would also cause loss of priming. In the present device the polnt of impelling energy is below water level and as close to the actual intake as possible. The exterior velocity of intake is thus equal to the pressure of the atmosphere plus IIU the head of water due to depth of immersion of the dig ing member, and is accentuated by the forci le shovel action of the shoe. The ascensional velocity may be maintained at 20' per second,-a..condition that would be impossible in a centrifugal ump. With this jet elevator gold and other heavy minerals can be maintainedin suspensionand carried upward, and the suction can be choke-fed with fines without loss of priming.

There is thus provided a combination of a. powerful vacuum, adjacent the intake of a water jet, with a digging member having a powerful action and swinging through a ull stroke. In addition this coin ination is supplemented by the powerful downthrust, enabling the digging member to dig in, and also the special construction of the digging mem her or plow, which enables it to go through heavy and mixed ground. These and other advantages pertaining to the present invention reside not only in the specific features;

scribed, except as indicated in the appended with pressure water,

tically movable platform, power means for raising and loweringsaid platform, a'hydraulic jet elevator in said digging arm for elevating excavated material, and telescoping conduits, respectively supplying said jet cavated material.

2. In a pontoon dredge, the combination '7 of a power-controlled movable digging mem-' her with a hydraulic jet elevator, said dig,- ging member being equipped witha hollow plow-shaped shoe piece at its lower end, with a double-headed hollow trunnion piece at its upper end, two connecting pipes within the arm, one pipe being for the supply of pres: sure water to the jet, and the other for the upraise of the dredged material, these pipes and conveying away ex- I I being connected respectively at their upper ends to the respective arms of the trunnions' and at their lower ends to the shoe piece.

3. In a pontoon dredge, the combination of a rigid digging arm, a heavy shoeat the end thereof having a plow-shapedforward cutting edge and openings adjacent thereto, a vertically movable platform supporting said arm on trunnions, a. hydraulic jet elevator in the arm having its suction opening near said openings in the shoe, means for swing ing the arm and raising and lowering the platform, a conduit supplying to said jet elevator pressure Water, and a conduit for conveying away the excavated materials.

In testimony that I claim the foregoing, I I have hereunto set my hand this 8th day of March, 1926. r JOHN MALCOLM NICOL. 

